We have gone to WDW at memorial Day weekend and thought that it wasn't that bad. Its not "summer time" hot, its not "spring time" cool. I thought the crowds were managable, but we are veterns of the July 4th and Christmas week crowds.
That's what I figured. I guess I was hoping I would have better luck than some of the people trying to get concierge rooms in December (the rooms being gone at 9:01). It sounds like Memorial day may be just as busy.